Final answer:
The growth rate of Atlantic Canada's population is not explicitly detailed in the provided information, but immigration is noted as a significant factor in Canada's population growth. Specific data for Atlantic Canada would be required to accurately determine its growth rate in comparison to the national average or levels of outmigration.
Step-by-step explanation:
The student has asked about the population growth rate in Atlantic Canada. Based on the given information, we know that population growth in Canada has seen fluctuations and can be influenced by various factors, such as immigration, which contributes to economic and population growth. Comparing to the national average, it is not explicitly stated, but immigration has a notable impact, and given the historical migration trends and the current demographic shifts in Canada, it's possible to infer about the growth patterns in different regions.
However, without more specific data about Atlantic Canada, we cannot conclusively determine if the growth rate is less than, more than, or equal to the national average, nor can we gauge the outmigration levels with certainty. Still, it is known that generally, population growth in Canada has been supported by high levels of immigration, and Atlantic Canada, specifically, may have different trends due to its geographical and economic attributes.
Concerning the option mentioning 'outmigration', emigration naturally decreases population size and growth rate. Thus, if Atlantic Canada experiences low outmigration, this would contribute positively to its population growth. Nevertheless, specific data for Atlantic Canada would be required to choose the most accurate option among the provided choices.